Mechanical and Civil Engineering Seminar

The July 4-5, 2019 Ridgecrest Ruptures

The M6.4 and M7.1 earthquakes in early July 2019 were the largest earthquakes in southern California in two decades. Technological advances provide new observational clarity on the manifestation of these events in time and space and an opportunity to assess the community's scientific response capabilities. In this talk I will begin with an overview of the earthquake sequence, highlighting the observations of the scientific and engineering communities made quickly after the events. I follow with a presentation of the characteristics of the surface ruptures, focusing on a comparison of the distribution and form of ground deformation in field- and satellite-based observations, including pixel tracking and InSAR results provided by colleagues at JPL and CGS. I find that the average displacement, rupture length, and geometry of the Ridgecrest ruptures fit well in existing empirical relationships, and the detail afforded in modern observational data warrant new metrics to describe the variability of surface fault rupture.